Fan control system and method and heat dissipation system of electronic equipment

ABSTRACT

A fan control system having a temperature sensor, a temperature control module, a first logic, a second logic and a fan control circuit is provided to resolve the heat problem and the noise problem. The temperature sensor is used to detect the operation temperature of an integrated circuit, and the temperature control module receives the detected temperature to output a first logic signal. According to the first logic signal, the first logic outputs a second logic signal. One or more than one operation relationship between the fan rotation speed and operation temperature is set up in the second logic. According to the second logic signal, a curve showing the relationship between the fan rotation speed and the operation temperature is selected, and a second control signal is output. The control circuit can thus output a voltage to make the fan rotating, in responding to the second control signal.

BACKGROUND OF THE INVENTION

1. Field of Invention

The present invention relates in general to a fan control system, and more particularly, to a fan control system that performs heat dissipation according to various temperature curves in an electronic device or an information-processing device.

2. Related Art

The advancement of computer technology has consequently increased the energy consumption. Currently, large-size heat sinks have been used to dissipate heat by natural convection or large-size fans have been used to aid in air convection. Alternatively, small- or medium-size heat sinks have been used in combination with small-size fans to dissipate heat by air convection within an enclosure. Other dissipation systems such as a water-cooling heat dissipation system or a heat pipe have been proposed as well. In the typical personal computer, the electronic apparatus or information processing devices, combination of heat sink and fan are mostly frequently used for heat dissipation. Therefore, the flow amount, pressure and bearing type are all factors that affect heat dissipation.

In the current heat dissipation system, the rotation speed of fan is controlled to provide adequate heat dissipation. The rotation speed of the fan rotation is often governed by temperature control. In a typical system, only one fan is used for heat dissipation. By detecting the temperature, the rotation speed can be determined from a pre-determined relationship between the temperature and the rotation speed. The operation range of the temperature curve is normally between the lowest 4.5-5 DCV (direct current voltage) and the highest 12-13 DCV.

As the functions provided by the computer system become more and more versatile, the noise problem caused by the fan rotation becomes more significant.

For example, when the user intends to watch a multi-medium film, the operation system is normally in stand-by state with a reduced heat source. According to the current fan control technique, the fan is low-speed rotating. In other words, after the computer system is switched on, the continuous rotation of the fan is maintained.

Most of the fans start rotation at a minimum speed or according to a single temperature curve. As the complexity or the operation mode of the system increases, a single temperature curve is insufficient to meet with the requirements of electronic products. The single temperature curve can't resolve the noise problem either.

It is therefore a substantially need to provide a fan operation system, operative to work in a more complex operation environment without causing significant noise.

BRIEF SUMMARY OF THE INVENTION

A fan control system and a fan control method are provided to resolve the drawbacks as mentioned above.

The fan control system for an electronic apparatus includes one or more temperature sensors, a temperature control module, a first logic, a second logic, at least one control circuit and at least one fan. The electronic apparatus includes a motherboard, a power supply for supplying operation power of the system and one or more integrated circuits installed in the motherboard for assisting the system operation. The temperature sensor is used to detect the operation temperature of at least one component of the integrated circuit. The temperature control module in communication with the temperature sensor is used to output a first logic signal corresponding to the detected temperature and a first control signal corresponding to operation status of the electronic apparatus. The first logic in communication with the temperature control module is used to output a second logic signal corresponding to the first logic signal and the first control signal. The second logic in communication with the first logic includes at least one relationship of fan rotation speed and operation temperature and is operative to output a second control signal according to the relationship of fan rotation speed and operation temperature corresponding to the first logic signal and the first control signal. The control circuit is used to receive the second control signal and to output a voltage corresponding to the second control signal. The fan is driven to rotate by the voltage.

According to the present invention, the fan is installed in a power supply of the electronic apparatus, which provides power to the fan.

According to the present invention, a plurality of fans is installed at various heat-generating components of the electronic apparatus, and the motherboard provides power to the fans.

Furthermore, the fan control method of an electronic apparatus includes detecting the operation temperature of the integrated circuit, generating a first logic signal according to the operation temperature and a first control signal according to operation status of the integrated circuit, generating a second logic signal according to the first logic signal and the first control signal, selecting a relationship between fan rotation speed and temperature according to the second logic signal and generating a second control signal by the relationship, and outputting a voltage according to the second control signal to make a fan to rotating.

According to the first logic signal, the first logic outputs a second logic signal. One or more than one operation relationship between the fan rotation speed and operation temperature is set up in the second logic. According to the second logic signal, a curve showing the relationship between the fan rotation speed and the operation temperature is selected, and a second control signal is output. The control circuit can thus output a voltage to make the fan to rotating, responding to the second control signal.

The objectives of the present invention will become obvious to those of ordinary skill in the art after reading the following detailed description of preferred embodiments.

It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

These, as well as other features of the present invention, will become more apparent upon reference to the drawings therein:

FIG. 1 is a block diagram of a fan control system of an electronic apparatus;

FIG. 2A shows a voltage-temperature curve used for the fan control system;

FIG. 2B shows another voltage-temperature curve used for the fan control system;

FIG. 2C shows another voltage-temperature curve used for the fan control system;

FIG. 2D shows another voltage-temperature curve used for the fan control system; and

FIG. 3 shows the configuration of operation signal for the fan control system.

DETAILED DESCRIPTION OF THE INVENTION

Detailed reference will now be made to the preferred embodiments of the present invention, examples which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or similar parts.

Referring to FIG. 1, the fan control system of an electronic device includes one or more temperature sensors, a temperature control module 10, a first logic 20, a second logic 30 and one or more control circuits 40. For the convenience of discussion, the temperature sensors are referred to as the first, the second and the third temperature sensors, and the signals output thereby are referred as the first, the second and the third temperature signals, respectively.

As shown, the temperature module 10 and the first logic 20 are installed on a motherboard 100 of the electronic device, while the second logic 30 and the control circuit 40 are installed in a power supply 200 of the system.

Typically, the motherboard 100 includes a central processing unit, serving as a system operation core, memory, display card, sound card, network card and other integrated circuit chips for assisting the system operation. In addition, the television card or video card and others can also be installed to provide more functions of the system. In one embodiment, the motherboard 100 may include more than one integrated circuit as the operation core. For example, the motherboard 100 may be installed in a housing that comprises a power supply 200 for supplying operation power of the system. In addition, a plurality of heat dissipation fans may be installed in the housing for dissipating heat generated during operation. In addition to the power supply, the heat dissipation fan is also easily installed at the integrated circuit, to generate heat, such as the central processing unit. The power source of the fan is provided from the power supply or the source supply module on the motherboard, for example. The heat dissipation fan rotates with a speed according to the temperature, detected by the temperature sensor.

The electronic device includes a personal computer, a server, a video game, a multimedia computer, a multimedia player, or a personal video recording system (PVR), for example.

One or more temperature sensors may be installed on the display card, the television card, the central processing unit and the power source.

As shown in FIG. 1, one or more temperature sensors are used to detect the operation temperatures of the integrated circuit such as the central processing unit and the television card.

The function and operation for each of the above devices are described as follows.

The temperature control module 10 is in communication with the temperature sensor to receive the temperature detected thereby. Upon receiving the detected temperature, a first logic signal TEMP1-3 is generated and output by the temperature control module 10. The number of the first logic signals corresponds to the number of temperature sensors. The temperature control module 10 includes an input/output chip (super I/O) and more than one thermal control integrated circuit (IC) for receiving the temperature, detected by the temperature sensors. Alternatively, the temperature control module 10 may include either the super I/O or the thermal control IC. The super I/O is operative to output a detection source circuit signal to the first logic 20 to aid the first logic 20, to determine whether the received temperature is output from the super I/O or the thermal control IC.

The thermal control module 10 may also output a first control signal S1 to the first logic 20 to inform the first logic 20 with the current operation mode. The bit number of the first control signal S1 determines the number of operation modes for the system. When the first control signal S1 includes only one bit, the system includes two operation modes. When the first control signal S1 includes two bits, there are four operation modes available for the system. Therefore, the bit number of the first control signals S1 can be configured according to the system complexity and specific requirement.

In one embodiment, the first control signal S1 output by the temperature control module 10 is controlled by a basic input/output system (BIOS) of the system. It is known in the art that the temperature control module 10 can be connected to the BIOS via system management (SM bus).

The first logic 20 is in communication with the temperature control module 10 to output a second logic signal L1 in response to the first logic signal TEMP1-3 and the first control signal S1.

The second logic 30 is connected to the first logic 20. A rotation speed-temperature relationship for one or more than one fan is installed in the second logic 30. According to the relationship corresponding to the second logic signal L1, a second control signal S2 is output by the second logic 30.

The control circuit 40 is connected to the second logic 30 to drive the fan rotation in response to the second control signal S2. Each control circuit corresponds to one specific voltage-temperature curve. The voltage includes the applied voltage for making the fan to rotating. The first logic 20, the second logic 30 and the control circuit 40 can be assembled by any electronic devices such as transistors and logic gates.

In one embodiment, the first logic 20 and the second logic 30 include an independent electronic circuit or integrated circuit. Or alternatively, the first and second logics 20 and 30 can be integrated into a single circuit or integrated circuit.

In the embodiment as shown in FIG. 1, the second logic 30 and the control circuit 40 include independent circuits or integrated circuits. However, the second logic 30 and the control circuit 40 can be integrated into a single circuit or integrated circuit as desired.

FIGS. 2A to 2D show several exemplary voltage-temperature curves for the control circuits 40. In FIG. 2A, a two-step voltage-temperature curve with a smooth transition is illustrated. In FIG. 2B, the control circuit 40 corresponds to a linear voltage-temperature curve. In FIG. 2C, a two-step voltage-temperature curve with abrupt transition is illustrated. In FIG. 2D, the multiple-step voltage-temperature curve is illustrated. It will be appreciated that the voltage-temperature curve may vary according to specific requirements.

The operation of the fan control system will be further explained herein, with reference to FIG. 3 that illustrates the relationship between the temperature sensor and the control signal.

As mentioned above, the electronic device includes one or more than one temperature sensor installed in the central processing unit and television card, for example. In the normal operation module of the system, a first control signal S1, such as the signal “0” as shown in FIG. 3, is output from the temperature control module 10 to the first logic 20. The temperature sensor installed at the central processing unit and the temperature sensor installed at the television card will receive different temperatures received by the temperature control module 10. The detected temperatures are output to the first logic 20, which then convert the detected temperatures into detection logic signals. In the embodiment as shown in FIG. 3, four temperature sensors are installed to generate four different temperature signals, converted into the detection logic signals by the first logic 20.

When the signals detected by the temperature sensor are <X° C., <Y1° C., <Y2° C. and <Z° C., the first logic 20 generates a second logic signal as “00” corresponding to the first logic signal “0”, such, that the second logic 30 is operative to output a second control S2, responding to the second logic signal “00”.

When the signals detected by the temperature sensor are >X° C., <Y1° C., <Y2° C. and <Z° C., the first logic 20 generates a second logic signal as “11” corresponding to the first logic signal “1”, such that the second logic 30 is operative to output a second control S2 responding to the second logic signal “11”.

The second logic 30 includes various temperature-voltage curves stored therein. The temperature-voltage curves correspond to respective second logic signal. For example, when the second logic signal is “00”, the second control signal corresponding to “00” will be output by the second logic, to provide a corresponding voltage allowing the control circuit 40 to drive the fan to rotate.

While the present invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those of ordinary skill in the art that the various changes in form and details may be made herein without departing from the spirit and scope of the present invention as defined by the appended claims. 

1. A fan control system for an electronic apparatus that includes one or at least one integrated circuits, the system comprising: at least one temperature sensor arranged correspondingly to some or all of the integrated circuits, for detecting operation temperature of the corresponding integrated circuits; a temperature control module connected to the temperature sensors, the temperature control module being operative to output a first logic signal corresponding to the detected temperature, and a first control signal corresponding to the electronic apparatus; a first logic connected to the temperature control module, the first logic being operative to output a second logic signal corresponding to the first control signal; a second logic connected to the first logic, including at least one fan rotation speed-operation temperature relationship stored therein, the second logic being operative to output a second control signal based on the corresponding fan rotation speed-operation temperature relationship; and at least one control circuit to receive the second control signal and provide a voltage corresponding to the second control signal.
 2. The system of claim 1, wherein the temperature control module and the first logic are arranged on a motherboard, and the second logic and the control circuit are arranged in a power supply of the electronic apparatus.
 3. The system of claim 1, wherein the temperature control module comprises a super input/output chip.
 4. The system of claim 1, wherein the temperature control module comprises a super input/output chip and at least one thermal control integrated circuit operative to receive the temperature detected by the temperature sensors.
 5. The system of claim 1, wherein the temperature control module comprises at least one thermal control integrated circuit operative to receive the temperature detected by the temperature sensors.
 6. The system of claim 1, wherein the bit number of the first logic signal corresponds to the number of the temperature sensors.
 7. The system of claim 1, wherein the first and second logics are independent electronic or integrated circuits.
 8. The system of claim 1, wherein the first and second logics are integrated into a single electronic or integrated circuit.
 9. The system of claim 1, wherein the second logic and the control circuit are independent electronic or integrated circuits.
 10. The system of claim 1, wherein the second logic and the control circuit are integrated into a single electronic or integrated circuit.
 11. A heat dissipation system of an electronic apparatus having one or at least one integrated circuits, comprising: at least one temperature sensor arranged correspondingly to some or all of the integrated circuits, for detecting the operation temperature of the corresponding integrated circuits; a temperature control module in communication with the temperature sensor to output a first logic signal corresponding to the detected temperature and a first control signal corresponding to operation status of the electronic apparatus; a first logic in communication with the temperature control module to output a second logic signal corresponding to the first logic signal and the first control signal; a second logic in communication with the first logic, the second logic including at least one relationship of fan rotation speed and operation temperature and being operative to output a second control signal according to the relationship of fan rotation speed and operation temperature corresponding to the first logic signal and the first control signal; at least one control circuit to receive the second control signal and to output a voltage corresponding to the second control signal; and at least one fan, each connected to the corresponding control circuit, driven to rotate by the corresponding voltage.
 12. The system of claim 11, wherein the temperature control module and the first logic are arranged on a motherboard of the electronic apparatus, and the second logic and the control circuit are arranged in a power supply of the electronic apparatus.
 13. The system of claim 11, wherein the fan is arranged in a power supply of the electronic apparatus which provides power to the fan.
 14. The system of claim 11, wherein the fans selectively arranged correspondingly to some or all of the integrated circuits, and a motherboard of the electronic apparatus provides power to the fans.
 15. The system of claim 11, wherein the temperature control module comprises a super input/output chip.
 16. The system of claim 11, wherein the temperature control module comprises a super input/output chip and a thermal control integrated circuit operative to receive the detected temperature.
 17. The system of claim 11, wherein the bit number of the first logic signal corresponds to the number of the temperature sensors.
 18. The system of claim 11, wherein the first logic and the second logic are independent electronic or integrated circuits.
 19. The system of claim 11, wherein the first and second logics are integrated into a signal electronic or integrated circuit.
 20. The system of claim 11, wherein the second logic and the control circuit are independent electronic or integrated circuits.
 21. The system of claim 11, wherein the second logic and the control circuit are integrated into the same electronic or integrated circuit.
 22. A fan control method for an electronic apparatus that has at least one integrated circuit, the method comprising: detecting the operation temperature of the at least one integrated circuit; generating a first logic signal according to the operation temperature and a first control signal according to operation status of the integrated circuit; generating a second logic signal according to the first logic signal and the first control signal; selecting a relationship between fan rotation speed and temperature according to the second logic signal and generating a second control signal by the relationship; and outputting a voltage according to the second control signal to drive a fan to rotate. 